<div>
    This monitors the available virtual memory space of the computer (commonly known as "swap space"),
    and if it goes below a threshold, the slave is marked offline.

    <p>
    The exact definition of the swap space is platform dependent.

    <ul>
    <li>
    On Windows, this value is
    <a href="http://msdn.microsoft.com/en-us/library/aa366589(VS.85).aspx">the available space in the page file</a>,
    but because Windows is capable of expanding the page file size automatically, the value doesn't really mean much.

    <li>
    On Linux, this value is obtained from <tt>/proc/meminfo</tt>.

    <li>
    On other Unix systems, this value is obtained by executing the <tt>top</tt> command.
    </ul>

    <p>
    If you have an operating system where this value is not reported, please let us know so that we can improve this.
</div>